This invention relates to a forceps stopcock to close the port of an endoscope channel allowing for the insertion of medical operation instruments.
When a medical examination or operation is carried out by means of an endoscope, the endoscope is generally inserted into the patient's coeliac cavity. In this case, various operations are taken through the endoscope. For instance, a medical solution is injected into the patient's coeliac cavity or his affected portion is excised or sampled. To this end, therefore, the endoscope is provided with an insertion channel allowing for the insertion of instruments used to carry out the above-mentioned medical operations. During the application of the endoscope, however, it sometimes happens that air or filth held in the coeliac cavity leaks to the outside through the insertion channel. In such a case, the leakage of air or filth from the coeliac cavity has hitherto been prevented by fitting a forceps stopcock to the insertion channel port. This stopcock is prepared from elastic material such as rubber and provided with a slit allowing for the insertion of a medical operation instrument. The slit is usually closed in an airtight fashion, and is opened when forcefully pushed by a medical operation instrument, thereby enabling the instrument to be inserted into the channel.
When, however, a medical operation instrument is inserted into the slit, it sometimes happens that gaps appear between the slit and the medical operation instrument, resulting in the leakage of air or filth conducted from the patient's coeliac cavity.
To avoid the above-mentioned drawbacks, therefore, a forceps stopcock has been proposed which is constructed by superposing an elastic stopcock having a slit and an elastic stopcock having a through hole with a smaller diameter than that of a medical operation instrument on each other. This composite plug is constructed by tightly holding the pair of superposed plugs by means of a tightening ring, and is securely held in the insertion channel port by means of a fixed ring. However, such a composite forceps stopcock has the drawback that difficulties are presented in fitting the stopcock into the endoscope, taking it out of the insertion channel port and cleaning the whole stopcock assembly.